Revert "PCI: allocate bus resources from the top down"

This reverts commit b126b4703afa4010b161784a43650337676dd03b.

We're going back to the old behavior of allocating from bus resources
in _CRS order.

Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 5 insertions, 48 deletions

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 5624db8c9ad0..69546e9213dd 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -64,49 +64,6 @@ void pci_bus_remove_resources(struct pci_bus *bus)
         }
 }
 
-/*
- * Find the highest-address bus resource below the cursor "res".  If the
- * cursor is NULL, return the highest resource.
- */
-static struct resource *pci_bus_find_resource_prev(struct pci_bus *bus,
-                                                   unsigned int type,
-                                                   struct resource *res)
-{
-        struct resource *r, *prev = NULL;
-        int i;
-
-        pci_bus_for_each_resource(bus, r, i) {
-                if (!r)
-                        continue;
-
-                if ((r->flags & IORESOURCE_TYPE_BITS) != type)
-                        continue;
-
-                /* If this resource is at or past the cursor, skip it */
-                if (res) {
-                        if (r == res)
-                                continue;
-                        if (r->end > res->end)
-                                continue;
-                        if (r->end == res->end && r->start > res->start)
-                                continue;
-                }
-
-                if (!prev)
-                        prev = r;
-
-                /*
-                 * A small resource is higher than a large one that ends at
-                 * the same address.
-                 */
-                if (r->end > prev->end ||
-                    (r->end == prev->end && r->start > prev->start))
-                        prev = r;
-        }
-
-        return prev;
-}
-
 /**
  * pci_bus_alloc_resource - allocate a resource from a parent bus
  * @bus: PCI bus
@@ -132,10 +89,9 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
                                           resource_size_t),
                 void *alignf_data)
 {
-        int ret = -ENOMEM;
+        int i, ret = -ENOMEM;
         struct resource *r;
         resource_size_t max = -1;
-        unsigned int type = res->flags & IORESOURCE_TYPE_BITS;
 
         type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 
@@ -143,9 +99,10 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
         if (!(res->flags & IORESOURCE_MEM_64))
                 max = PCIBIOS_MAX_MEM_32;
 
-        /* Look for space at highest addresses first */
-        r = pci_bus_find_resource_prev(bus, type, NULL);
-        for ( ; r; r = pci_bus_find_resource_prev(bus, type, r)) {
+        pci_bus_for_each_resource(bus, r, i) {
+                if (!r)
+                        continue;
+
                 /* type_mask must match */
                 if ((res->flags ^ r->flags) & type_mask)
                         continue;